I'm afraid I don't know anything about the Princess line, but it looks like Luisa has offered a lot of knowledge.
As far as the bottle/potty-training stuff, let me just support you in doing what you think is best. I can't, for the life of me, figure out why people become so incensed at stuff like this. It doesn't infringe on them, at all!
I have two children, one borne to me, the other adopted. My birthchild nursed until he was four years, nine months. He was not potty trained until he was three and a half, because I didn't see the need to press the issue until he indicated some interest, and appropriate developmental readiness. He is now 15, scored in the 95th percentile of *sophomores* (as a freshman) on two of the three sections of the PSAT, and was given an award by the high school just yesterday as one of the "MVP's" of his class -- students who should serve as role models for the other students for their scholastic achievement, citizenship, and work ethic. He seems to have turned out okay. :-)
My daughter was adopted at nearly four years of age. She had been potty trained at two, and we had *terrible* issues of anxiety around this. I really think she was done a disservice. Similarly, she wanted a bottle for a couple of years after she came. She had been weaned to a cup at a very young age, and still needed that oral comfort of the sucking. I gave it to her. I can well imagine what some of the people who have posted here would have commented about that! Fortunately, a few years of meeting *her* needs, as opposed to forcing that for which she wasn't prepared upon her, has made a big difference, and she, too, is doing very well--- got her report card yesterday, and she's made the dean's list this quarter, and everyone always comments on how hard-working and polite she is.
Don't let the others get you down. Look at your children. Are they healthy? Are they happy? Are they developmentally where they should be (given their individual issues)? Do they respond to structure and consequences? If the answer is yes to all of these, I'd say you are doing a great job.